Having tried a few radiator cleaners this Liqui Moly is the best I've tried so far. Had a 206 that had head gasket failure in its past. The coolant hoses were lined with a horrible sticky paste. Used as per instruction car upto operating temp heater on etc then pour in and leave to run for 10-30 mins. After 30 mins the inside of the pipes were like new. Will be buying from now on when needed. Always have one on the shelf